Tony wrote:

To avoid cracking at the joints in future you might choose to also use
some scrim tape over the joints.

Only problem with that is the tape will be going on to an already
finished surface, which I found is more trouble than it's worth.

You have to feather the finished surface over the tape and well onto the
finished wall. This leads to loads of dust and sanding and leaves the
"new" bit of wall higher than the wall either side. You just won't ever
get it not noticeable.

I'd give the tape a miss.
Even on tapered edge P.Board I found the tape troublesome when using
Jointing compound to "fill in" the joint.

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